1. Field of the Invention
This invention relates, in general, to building structures and, more specifically, to modular building structures and, even more specifically, to modular building structures adapted to be disposed partially or completely underground.
2. Description of the Prior Art
Building structures are typically supported on foundations of the pad footing or driven pile type. The stresses exerted on such foundations are resisted solely by the pad or pile surfaces. This has limited the location of buildings to areas having soil with a high bearing load capacity. Other types of soils, such as wet clay soils, have low bearing load capacities and do not provide sufficient support for typical building foundations thereby leaving vast areas unacceptable for the construction of buildings.
Building structures have also been devised with specially configured bases to resist subsurface vibrations or shocks of the type produced by earthquakes. Such building structures are typically constructed with a smoothly formed, continuous, arcuate or rounded bottom surface so as to increase the stability of the structure. Such base constructions, while effectively resisting subsurface vibrations and shocks, do little to permit the construction of such buildings on soils with low bearing load capacities.
Buildings have also been constructed in modular form from wood, metal or concrete pre-formed wall panels, frames and trusses which are assembled into a completed structure at the construction site. It is also known to construct modular building structures, tanks, etc., from concrete which is "shot" or sprayed over a frame which is then removed after the concrete sets or hardens.
It would be desirable to provide a modular building structure which can be constructed in soils having low bearing load capacities. It would also be desirable to provide a modular building structure which is adapted to be completely deployed underground. It would also be desirable to provide a modular building structure formed with a plurality of identically constructed modular units which may be interconnected in a variety of configurations and used on varying terrains. Finally, it would be desirable to provide a modular building structure which is economically and quickly formed of concrete which is "shot" or sprayed about a frame.